This application relates generally to dry fertilizer compositions and methods for making the compositions. More specifically, the invention relates to a dry fertilizer composition having improved anti-caking and flow properties and a method for making the dry fertilizer compound.
Dry, granular fertilizers are more extensively used because they are less expensive and easier to handle and apply than liquid fertilizers. However, because the dry, granular fertilizers tend to be hygroscopic, that is, they easily absorb moisture, the dry fertilizers will cake easily. Maintenance of a free flowing nitrogen-containing material in its manufactured form, either crystalline, granular or pellets, under long term storage conditions, has long been a problem in the art. It is usually recommended that the fertilizer should always be handled and stored in ways to avoid contact with water, humidity, or damp surfaces. Caking prevents the dry material from flowing easily. Caking also prevents the fertilizer from being handled, stored or transported easily. Caking can also cause breakage of handling, storage, or transportation apparatus. In addition, caking of the fertilizer can render the fertilizer unsuitable for its intended use.
Dry fertilizer also has the tendency to fracture into smaller particles resulting in a substantial amount of dust being created when the fertilizer is handled, transported and applied to the soil in its intended use. The presence of dust can adversely affect the workers who handle the dry fertilizer, if such dust is inhaled. Thus, safety precautions need to be taken when working with dry fertilizers that create large quantities of dust.
Many have tried to control the dust and prevent caking through the use of conditioning agents applied to the fertilizer. For example, anti-caking properties have been imparted to fertilizer particles through the individual use of lignosulfonate, tripotassium phosphate, surfactants, kaolin, zeolite, clay, calcium oxide, calcium hydroxide, cement, fly ash, magnesium nitrate, or alkyl sulfates, to name a few. Despite the long standing problem, the market has not yet developed a satisfactory solution which provides a free-flowing (anti-caking), and dust controlled dry, granular fertilizer.
The present invention describes a composition which has as its base a dry, granular fertilizer and to which is added a flowing agent and further to which is added a hydrophobic agent. The present invention also describes a method for making this composition.
The present invention exhibits significantly improved anti-caking properties over untreated fertilizers. In addition, the present invention controls dust significantly more than untreated fertilizers. Thus, it is an object of the present invention to provide a treated fertilizer that has improved anti-caking properties and significantly reduced production of dust.
These and other objects, features, and advantages of the invention will become apparent from the following best mode description, the drawings and the claims.